MOD adds in Skyrim is a lot of realism. Now all the NPCS in rain will wear a hood or run home (of course you can configure). The same situation is with the snow storms that adds this mod. Also now on your character will be water droplets (or will drain water) in rain or after bathing. Another realistic innovation is that in cold regions of Skyrim mouth NPCS will go couples.All this can be customized by using spells that can be found in the list of your magic.